FLORIDA KEYS -- Already suffering from Lou Gehrig's disease, Key West banker and philanthropist Gib Peters undertook a seven-month solo voyage up the Intercostal Waterway in 2004.
Remarkably, though the disease was progressively robbing Peters of muscle control, he accomplished his goal, making it safely in his 29-foot Wellcraft from Key West to the Hudson River. Eighty-four days after he returned to Key West, Peters died.
Now, with the help of a $715,000 funding contract with the Centers for Disease Control, Peters' physician Walter Bradley has begun a research project to examine if residents of areas like the Florida Keys, where blue-green algae blooms are common in the nearby waters, have an increased risk of becoming afflicted by Lou Gehrig's disease.
Over the next two years, Bradley, a University of Miami neurologist, will compare the incidence of Lou Gehrig's disease, also known as amyotrophic lateral sclerosis, or ALS, in areas near algae-laden waters to its incidence in areas that are further away from such water bodies.
He'll augment that work with surveys designed to tease out any patterns, such as seafood consumption habits, which distinguish the personal histories of people who contract the disease from those who don't.
Bradley will conduct his Florida portion of the study in coordination with Dartmouth University neurologist Elijah Stommel, who will be looking into the same question in Vermont and New Hampshire.
Their work will follow up on a more limited 2011 study of Stommel's, in which he found that in targeted areas of northern New England, people who lived within a half-mile of bodies of water where blue-green algae blooms occur were 2.5 times as likely to suffer from Lou Gehrig's disease as those who do not.
"If you're out there every day fishing and you're eating the fish and breathing in the air, you might be increasing your odds [of contracting ALS] tremendously if you have a genetic predisposition," Stommel said.
Lou Gehrig's disease is a progressive degenerative disorder that affects nerves in the brain and spinal column. Its victims remain mentally alert to the very end, but they eventually lose control of all voluntary muscle movement, robbing them of their ability to speak, walk and, finally, to breathe. ALS sufferers typically die from respiratory failure within five years.
The disease remains rare in the United States, where 2.5 people per 100,000 develop it in a given year. ALS is the cause of approximately one out of every 350 deaths in the U.S. among people between the ages of 50 and 70, according to Bradley.
In some other parts of the world, however, it is more common. For example, a study of the indigenous Chamarro people in post-World War II Guam showed incidence rates up to 100 times of those found in the United States.
Scientists hypothesize that the reason was the Chamarro's diet, which relied heavily on a fruit bat species that carries large amounts of a toxin called BMAA (beta-N-methylamino-l-alanine). The bats were picking up the toxin from the consumption of cycad seeds, which are laden with cyanobacteria, a compound known more commonly in the Keys as blue-green algae. Subsequent studies have shown that in other areas around the world where the incidence of ALS is high diets are consistently heavy in BMAA-laden food.
For Floridians, and residents of the Keys in particular, that might matter. In a 2010 paper, University of Miami researchers found that Florida Bay pink shrimp were carrying as much BMAA as the fruit bats that the villagers of Guam were eating. ALS scientists also say breathing the air near cyanobacteria blooms is another potential mechanism for internalizing the bacteria.
To date, the linkage between BMAA and Lou Gehrig's disease remains only a well-supported hypothesis, Stommel said. Certainty would only come from injecting the toxin in lab animals, preferably a primate, and then studying the results. It's also remains uncertain if BMAA can work its way from cyanobacteria up the marine food chain.
But by studying the demographics of ALS in Florida, Bradley is hoping to determine if there is a correlation between what he calls "ALS hotspots" and areas where blue-green algae blooms are especially prevalent.
"My guess is that we are going to find a larger proportion of people in the Keys that have ALS than the rest of Florida," he said.